CN108557845A - A kind of production method of sodium sulfite - Google Patents
A kind of production method of sodium sulfite Download PDFInfo
- Publication number
- CN108557845A CN108557845A CN201810193113.6A CN201810193113A CN108557845A CN 108557845 A CN108557845 A CN 108557845A CN 201810193113 A CN201810193113 A CN 201810193113A CN 108557845 A CN108557845 A CN 108557845A
- Authority
- CN
- China
- Prior art keywords
- sulfuric acid
- sodium sulfite
- concentration
- sulfur dioxide
- sulphur
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 title claims abstract description 45
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 25
- 235000010265 sodium sulphite Nutrition 0.000 title claims abstract description 23
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 70
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 claims abstract description 50
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 41
- 239000002699 waste material Substances 0.000 claims abstract description 27
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims abstract description 25
- 239000005864 Sulphur Substances 0.000 claims abstract description 20
- PQUCIEFHOVEZAU-UHFFFAOYSA-N Diammonium sulfite Chemical compound [NH4+].[NH4+].[O-]S([O-])=O PQUCIEFHOVEZAU-UHFFFAOYSA-N 0.000 claims abstract description 7
- 238000001704 evaporation Methods 0.000 claims abstract description 7
- 230000008020 evaporation Effects 0.000 claims abstract description 7
- 238000010521 absorption reaction Methods 0.000 claims abstract description 5
- 238000005119 centrifugation Methods 0.000 claims abstract description 5
- 238000002425 crystallisation Methods 0.000 claims abstract description 5
- 230000008025 crystallization Effects 0.000 claims abstract description 5
- 238000001035 drying Methods 0.000 claims abstract description 5
- 238000006386 neutralization reaction Methods 0.000 claims abstract description 5
- 238000001816 cooling Methods 0.000 claims abstract description 3
- 238000006722 reduction reaction Methods 0.000 claims abstract description 3
- 238000000034 method Methods 0.000 claims description 10
- 239000003014 ion exchange membrane Substances 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 239000002253 acid Substances 0.000 claims description 3
- 239000007788 liquid Substances 0.000 claims description 3
- 238000001914 filtration Methods 0.000 claims description 2
- 241000790917 Dioxys <bee> Species 0.000 claims 1
- 238000012545 processing Methods 0.000 description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 4
- 238000005265 energy consumption Methods 0.000 description 4
- 238000005260 corrosion Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 3
- 238000009776 industrial production Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 238000005554 pickling Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 239000011593 sulfur Substances 0.000 description 2
- 229910052717 sulfur Inorganic materials 0.000 description 2
- -1 aromatic nitration Substances 0.000 description 1
- 238000006172 aromatic nitration reaction Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- XLYOFNOQVPJJNP-ZSJDYOACSA-N heavy water Substances [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 229910021645 metal ion Inorganic materials 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
- 239000001038 titanium pigment Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/14—Preparation of sulfites
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Treating Waste Gases (AREA)
- Gas Separation By Absorption (AREA)
Abstract
The invention discloses a kind of production methods of sodium sulfite to include the following steps:S1, by waste sulfuric acid solution through row concentration, so that sulfuric acid concentration expressed in percentage by weight is more than 65%, then according to after concentration sulfuric acid solution and sulphur weight ratio be 5:1 ratio adds sulphur in the middle to sulfuric acid solution, is then heated to 250 300 degrees Celsius of progress reduction reactions, generates sulfur dioxide gas;S2, the sulfur dioxide gas generated in S1 is carried out after cooling down recovered steam, then sulfur dioxide gas is made to enter in sulphur removal reactor, eliminated sublimed sulfur in gas, obtain purer sulfur dioxide;S3, the pure sulfur dioxide gas obtained in S2 is entered in absorption tower, neutralization reaction occurs with sodium hydroxide solution, obtains sodium sulfite solution;S4, the ammonium sulfite solution obtained in S3 is obtained into sodium sulfite product after concentration and evaporation, crystallization, centrifugation and drying.
Description
Technical field
The present invention relates to chemical field, especially a kind of production method of sodium sulfite.
Background technology
In recent years, with the fast development of Chinese national economy, to demands such as the basic chemicals such as sulfuric acid in industrial production
Increase year by year, domestic annual sulfuric acid consumption figure is discharged in 9Mt or more, a larger part in the form of Waste Sulfuric Acid, Waste Sulfuric Acid have with
Lower feature:
1. deriving from a wealth of sources, industry dispersion, in addition to main industries such as titanium dioxide, aromatic nitration, dyestuff, PETROLEUM PROCESSING and pickling iron and steels
Outside, also there is Waste Sulfuric Acid output in other tens kinds of chemical products productions;
2. Waste Sulfuric Acid total amount is larger, but the Waste Sulfuric Acid amount of individual enterprise's output is little, and Waste Sulfuric Acid amount is higher than the enterprise of 5 kt/a or more
Industry is less, only hundreds of tons of the annual Waste Sulfuric Acid quantum of output of many enterprises;
3. sulfur waste acid concentration is generally relatively low, impurity content is higher;
4. Waste Sulfuric Acid contains organic matter mostly, direct utilization is more difficult.
The method of existing processing Waste Sulfuric Acid is high-temperature cracking method technique, but is to invest big, energy the shortcomings that high-temperature cracking method
Consumption is high;In addition, due to F-, Cl- and metal ion in Waste Sulfuric Acid(Especially Na+)Be easy to cause equipment and pipeline corrosion and
Block, it is this under the conditions of equipment seriously corroded, maintenance cost is high, and leaks frequent occurrence, causes production accident, gives the life of enterprise
Production, safety belt carry out very big hidden danger.
Invention content
The present invention is to overcome the above situation insufficient, it is desirable to provide a kind of technical solution that can be solved the above problems.
A kind of production method of sodium sulfite, includes the following steps:
S1, by waste sulfuric acid solution through row concentration, so that sulfuric acid concentration expressed in percentage by weight is more than 65%, then according to the sulphur after concentration
Acid solution is 5 with sulphur weight ratio:1 ratio adds sulphur in the middle to sulfuric acid solution, is then heated to 250-300 degrees Celsius
Reduction reaction is carried out, sulfur dioxide gas is generated;
Specific reaction equation is as follows:S+2H2SO4→3SO2+2H2O
S2, the sulfur dioxide gas generated in S1 is carried out after cooling down recovered steam, then sulfur dioxide gas is made to enter sulphur removal
In reactor, sublimed sulfur in gas is eliminated, obtains purer sulfur dioxide;
S3, the pure sulfur dioxide gas obtained in S2 is entered in absorption tower, neutralization reaction occurs with sodium hydroxide solution, obtains
To sodium sulfite solution, specific reaction equation is as follows:SO2+2NaOH===Na2SO3+H2O;
S4, the ammonium sulfite solution obtained in S3 is obtained into sodium sulfite production after concentration and evaporation, crystallization, centrifugation and drying
Product.
As the preferred technical solution of the present invention, the sulphur in the S1 is added to sulfuric acid solution after filtration treatment and works as
In.
As the preferred technical solution of the present invention, pure sulfur dioxide gas is content in 15%-20% in the S2(Body
Product)Gas.
As the preferred technical solution of the present invention, sodium hydroxide solution is to go out slot alkali by ion-exchange membrane electrolyzer in the S3
Liquid is formulated with desalted water.
As the preferred technical solution of the present invention, it is described go out slot lye a concentration of 33%wt -36%wt.
As the preferred technical solution of the present invention, concentration and evaporation uses economic benefits and social benefits continuous concentration technique in the S4.
Compared with prior art, when beneficial effects of the present invention:
A kind of Waste Sulfuric Acid method that lower temperature processing industry generates is provided, entire processing step is simple, and cleaning reduces place
The threshold of Waste Sulfuric Acid is managed, not only low energy consumption, but also can avoid the corrosion and blocking of equipment and pipeline, solves the prior art
Requirement to equipment is high, high energy consumption and at producing the shortcomings of of high cost, and production ammonium sulfite, which uses in industrial processes, to be produced
Raw Waste Sulfuric Acid reduces the reluctant problem of Waste Sulfuric Acid in industrial production, more can be environmentally friendly, avoids generating secondary pollution etc.
Situation improves existence and the production environment of people, is a kind of technique made a silk purse out of a sow's ear, and goes out slot alkali using ion-exchange membrane electrolyzer
The input that liquid reduces enterprise to sodium hydroxide solution with the sodium hydroxide solution that desalted water is formulated, it is cost-effective.
Specific implementation mode
The technical scheme in the embodiments of the invention will be clearly and completely described below, it is clear that described implementation
Example is only a part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, this field is common
The every other embodiment that technical staff is obtained without making creative work belongs to the model that the present invention protects
It encloses.
Embodiment one
A kind of preparation method of ammonium sulfite, includes the following steps:
S1, the Waste Sulfuric Acid generated in production process of titanium pigment is chosen, content 35%, obtains content after concentration by 600 parts
74%, it 320 parts, is then constantly stirred during being heated to 270 degrees Celsius to 45 grams of sulphur of addition, equipment in waste sulfuric acid solution
It mixes, generates sulfur dioxide gas;
S2, after obtained sulfur dioxide gas is cooled down recovered steam, passing through in sulphur removal reactor, removing and distil in gas
Sulphur, obtain sulfur dioxide gas be content 15%(Volume)Gas.
S3, obtained sulfur dioxide gas is entered in absorption tower, is sent out with preprepared 33%wt sodium hydroxide solutions
Raw neutralization reaction, generates sulfurous acid solution.
S4, sulfurous acid is obtained after the sodium sulfite solution that S3 is obtained is carried out concentration and evaporation, crystallization, centrifugation and drying process
Sodium product.
Embodiment two
A kind of preparation method of ammonium sulfite, includes the following steps:
S1, the Waste Sulfuric Acid generated in pickling iron and steel production process is chosen, content 40%, is contained after concentration by 500 parts
Amount 80%, it is 200 parts, then continuous during being heated to 300 degrees Celsius to 30 grams of sulphur of addition, equipment in waste sulfuric acid solution
Stirring generates sulfur dioxide gas;
S2, after obtained sulfur dioxide gas is cooled down recovered steam, passing through in sulphur removal reactor, removing and distil in gas
Sulphur, obtain sulfur dioxide gas be content 20%(Volume)Gas.
S3, obtained sulfur dioxide gas is entered in absorption tower, with 36 %wt sodium hydroxide solutions of preprepared
Neutralization reaction occurs, generates sulfurous acid solution.
S4, sulfurous acid is obtained after the sodium sulfite solution that S3 is obtained is carried out concentration and evaporation, crystallization, centrifugation and drying process
Sodium product.
Embodiment three
Product testing is carried out to the sodium sulfite crystal generated in above-described embodiment, prepared sodium sulfite quality meets following table
It is required that.
The present invention provides a kind of production methods of sodium sulfite, and the sulfur waste of industry generation can be handled under lower temperature environments
Sour method, entire processing step is simple, and cleaning reduces the threshold of processing Waste Sulfuric Acid, and not only low energy consumption, but also can avoid setting
The corrosion and blocking of standby and pipeline, solve high requirement of the prior art to equipment, high energy consumption and at producing the shortcomings of of high cost,
Production ammonium sulfite uses the Waste Sulfuric Acid generated in industrial processes, reduces Waste Sulfuric Acid in industrial production and is difficult to handle
The problem of, it more can be environmentally friendly, situations such as avoiding generating secondary pollution, existence and the production environment of people are improved, is a kind ofization
The technique that waste be changed into values reduces enterprise using go out the slot lye and the sodium hydroxide solution that desalted water is formulated of ion-exchange membrane electrolyzer
Industry is cost-effective to the input of sodium hydroxide solution.
It is obvious to a person skilled in the art that invention is not limited to the details of the above exemplary embodiments, Er Qie
In the case of without departing substantially from spirit or essential attributes of the invention, the present invention can be realized in other specific forms.Therefore, no matter
From the point of view of which point, the present embodiments are to be considered as illustrative and not restrictive, and the scope of the present invention is by appended power
Profit requires rather than above description limits, it is intended that all by what is fallen within the meaning and scope of the equivalent requirements of the claims
Variation is included within the present invention.
Claims (6)
1. a kind of production method of sodium sulfite, which is characterized in that include the following steps:
S1, by waste sulfuric acid solution through row concentration, so that sulfuric acid concentration expressed in percentage by weight is more than 65%, then according to the sulphur after concentration
Acid solution is 5 with sulphur weight ratio:1 ratio adds sulphur in the middle to sulfuric acid solution, is then heated to 250-300 degrees Celsius
Reduction reaction is carried out, sulfur dioxide gas is generated;
S2, the sulfur dioxide gas generated in S1 is carried out after cooling down recovered steam, then sulfur dioxide gas is made to enter sulphur removal
In reactor, sublimed sulfur in gas is eliminated, obtains purer sulfur dioxide;
S3, the pure sulfur dioxide gas obtained in S2 is entered in absorption tower, neutralization reaction occurs with sodium hydroxide solution, obtains
To sodium sulfite solution;
S4, the ammonium sulfite solution obtained in S3 is obtained into sodium sulfite production after concentration and evaporation, crystallization, centrifugation and drying
Product.
2. a kind of production method of sodium sulfite according to claim 1, which is characterized in that the sulphur in the S1 passes through
It is added in sulfuric acid solution after filtration treatment.
3. a kind of production method of sodium sulfite according to claim 1, which is characterized in that pure dioxy in the S2
Change sulphur gas is content in 15%-20%(Volume)Gas.
4. a kind of production method of sodium sulfite according to claim 1, which is characterized in that sodium hydroxide is molten in the S3
Liquid is formulated with desalted water by the slot lye that goes out of ion-exchange membrane electrolyzer.
5. a kind of production method of sodium sulfite according to claim 4, which is characterized in that it is described go out slot lye concentration
For 33%wt -36%wt.
6. a kind of production method of sodium sulfite according to claim 1, which is characterized in that concentration and evaporation is adopted in the S4
With economic benefits and social benefits continuous concentration technique.
Priority Applications (1)
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CN201810193113.6A CN108557845A (en) | 2018-03-09 | 2018-03-09 | A kind of production method of sodium sulfite |
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CN201810193113.6A CN108557845A (en) | 2018-03-09 | 2018-03-09 | A kind of production method of sodium sulfite |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111003692A (en) * | 2019-12-13 | 2020-04-14 | 南京工业大学 | Sulfur dioxide recycling system and method |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105293534A (en) * | 2015-12-03 | 2016-02-03 | 攀枝花钢企欣宇化工有限公司 | Method for producing sodium sulfite solution by using sulfur dioxide gas |
CN106673017A (en) * | 2017-02-17 | 2017-05-17 | 四川省中明环境治理有限公司 | Environment-friendly production method for preparing sodium sulfite by utilizing sulfur to reduce waste sulfuric acid |
-
2018
- 2018-03-09 CN CN201810193113.6A patent/CN108557845A/en active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105293534A (en) * | 2015-12-03 | 2016-02-03 | 攀枝花钢企欣宇化工有限公司 | Method for producing sodium sulfite solution by using sulfur dioxide gas |
CN106673017A (en) * | 2017-02-17 | 2017-05-17 | 四川省中明环境治理有限公司 | Environment-friendly production method for preparing sodium sulfite by utilizing sulfur to reduce waste sulfuric acid |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111003692A (en) * | 2019-12-13 | 2020-04-14 | 南京工业大学 | Sulfur dioxide recycling system and method |
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TA01 | Transfer of patent application right |
Effective date of registration: 20181113 Address after: 414000 Wushi Industrial Zone, Pingjiang Industrial Park, Yueyang City, Hunan Province Applicant after: Hunan Yinqiao science and Technology Co., Ltd. Address before: 410300 No. 351, Dali Shang Group, Meijiao Village, Qingshanpu Town, Changsha County, Hunan Province Applicant before: Yang Yijia |
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Application publication date: 20180921 |